The study of 18 F-FDG PET/CT combing with HRCT in the diagnosis of pulmonary lymphangitic carcinomatosis

HE Haitao; LIU Shangda; ZHOU Pengcheng; XU Kangxiang; ZHU Ren

Abstract：Objective To assess the value of 18 F-FDG PET/CT combing with HRCT in the diagnosis of pulmonary lym-phangitic carcinomatosis (PLC). Methods Integrated PET/CT and HRCT images of 52 patients (32 men, 20 women,age, 32~82 years,mean age, 62 years) with PLC confirmed at the follow-up chest CT or histopathologic examination were analyzed retro-spectively. The mean standardized uptake value( SUVmean) ratio was measured in the affected lungs, the normal lungs, and the mediastinal blood pool. Abnormal PET activity in the lungs was assessed. The CT images was reviewed to determine the presence, size, location, and extent of PLC. The data were analyzed to determine the sensitivity and specifcity of PET/CT for PLC. Results Among the 52 patients with PLC, 30(58%), 22 (42%), 40 (77%), and 12 (23%) patients had unilateral, bilateral, focal, and diffuse PLC, respectively. The SUVmean ratioin the region of PLC(1. 34 ± 0. 68) was significantly greater than that in nor-mal lung (0. 55 ± 0. 17) ( P <0. 01). The SUVmean ratio ofbilateral lymphangitic lung to mediastinal blood pool that was (0. 82 ± 0. 28), (0. 73 ± 0. 29) respectively was significantly greater than that of normal lung to blood pool that was (0. 39 ± 0. 14)( P <0. 01). The specificity of PET/CT for PLC was 100%, and the sensitivity was 88%, additional diagnosis of PLC in 6 patients was made by HRCT in dependently. Conclusion 18 F-FDG PET/CT combing with HRCT has high specificity and sen-sitivity in the detection of PLC.